Learn advanced deco diving to 55m with expert instructors.
TDI Extended Range Diver Course (XR to 55m)
Push beyond entry-level technical diving with the TDI Extended Range Diver course in Phuket, Thailand. This advanced program trains divers to safely conduct extended range decompression dives to 55 metres (180 feet) using air, nitrox and oxygen, while mastering complex gas management, decompression planning and technical diving procedures.
The TDI Extended Range course represents a major step forward from Advanced Nitrox and Decompression Procedures, preparing divers for deeper, more demanding technical dives with increased responsibility and precision.
What Is the TDI Extended Range Diver Course?
The TDI Extended Range Diver course is an advanced technical diving certification designed to develop the skills required for deeper decompression diving beyond standard limits.
Divers learn to:
- plan and execute extended range dives
- manage increased decompression obligations
- operate with multiple gas mixtures
- maintain precision under higher task loading
This course bridges the gap between introductory technical training and deep trimix diving, making it a critical progression step.
Why Take Your Extended Range Course in Phuket?
Phuket offers some of the best conditions in Southeast Asia for technical diving training:
- Warm water and stable conditions
- Access to deeper offshore dive sites
- Access to deeper inland dive sites
- Ideal environment for decompression training
- Boat-based diving for efficient multi-dive days
Training in Phuket allows divers to develop real-world experience in practical extended range diving scenarios.
What You Will Learn
The TDI Extended Range course focuses on advanced decompression diving using air and enriched air nitrox.
Theory Topics Include:
- Advanced decompression theory
- Gas density and narcosis management
- Dive planning for extended range profiles
- Oxygen exposure and CNS tracking
- Multi-gas decompression strategies
- Emergency and bailout planning
- Equipment configuration for deep diving
- Practical Skills Developed During Training
This course significantly increases task loading and requires high-level control.
Skills Include:
- Advanced buoyancy and trim at depth
- Multi-stage cylinder management
- Complex gas switching procedures
- Decompression stop precision
- Valve shutdown and failure management
- SMB deployment and ascent control
- Team coordination and situational awareness
Equipment Used During the Course
Divers will train using a full technical configuration:
- Twinset or sidemount system
- Multiple stage/decompression cylinders
Common Challenges in Extended Range Diving
Moving into extended range diving introduces new levels of complexity.
Divers often face:
- increased task loading at depth
- managing narcosis on air
- maintaining buoyancy during long decompression stops
- gas planning accuracy
- situational awareness under stress
The course is designed to build these skills progressively and safely.
Who Is This Course For?
The TDI Extended Range Diver course is ideal for:
- certified decompression divers seeking deeper limits
- technical divers preparing for trimix training
- experienced divers wanting more challenging dives
- wreck and expedition divers
- divers looking to refine advanced technical skills
Course Prerequisites
To enrol in the TDI Extended Range course, you must:
- Be at least 18 years old
- Hold TDI Advanced Nitrox and Decompression Procedures certifications (or equivalent)
- Have a minimum of 100 logged dives
Course Structure (Minimum 5–6 Days)
- Day 1: Theory and dive planning
- Day 2: Skills development and assessment
- Days 3–6: Open water extended range dives
Training is conducted progressively to build confidence and precision at depth.
What Comes After Extended Range?
Completing the TDI Extended Range Diver course prepares you for:
Trimix diving
Advanced CCR training
Expedition-level technical diving
Deep wreck and cave exploration
Why Choose Us for Your TDI Extended Range Course?
- Highly experienced technical diving instructors
- Real extended range diving environments in Phuket
- Small group training for maximum focus
- Strong progression pathway into trimix and CCR
This course is not just about certification—it’s about becoming a capable and disciplined technical diver.
Contact Us
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